That's good advice, Zaph; thanks. I may reach out to her again.
I've noticed that the Ancestry messaging interface will display a tick mark when a message has been read, and this lets me know that one of the messages I've sent recently was read, even though he hasn't responded.
This person has a fairly unique name, and when I subsequently Googled it, I saw some news articles about a man and his spouse who served several years in federal (US) prison for tax fraud. So maybe sometimes it's a good thing when people don't respond, LOL.
I had a small public tree up on Ancestry when my DNA was initially uploaded; that's how that one man (let's call him Mr. Hoover) was able to identify my grandparents and then go bananas finding -- and adding to his tree -- everything to do with my mother's (completely unrelated to him) ancestors.
After Mr. Hoover announced to me that he'd narrowed down the possibilities of my father being Mr. X or Mr. Y, I was totally creeped out, and made my tree private. Even though my parents and I were 'private' on my tree, it's so easy now to trace people, thanks to online obits, etc.
It did make me wonder if sometimes I have creeped other people out when I've contacted them, asking, for example, if they are the grandchild of my grandfather's brother who moved to the US in the 1940s, and explaining that I've contacted them on the basis of information found in online obits, etc. Oh, dear.